1. Field of the Invention
The present invention relates to an actuator having a rotatable control shaft with a manually operated handle connected thereto and a device for generating a haptic perception signal when rotating the handle, in which the haptic signal generating device is developed in the form of a mechanical detent assembly having an annular body and at least one detent element engaging teeth on an inner surface of the annular body.
2. Background Art
Rotating actuators are used, for example, with data input devices in which a cursor control can be implemented at different menu levels, for example, by rotating the rotating actuator and, where appropriate, by pushing or swiveling the actuator. For example, such a rotating actuator may be part of a joystick. This type of rotating actuator is known from DE 197 12 049 A1. In this known rotating actuator, a drive for generating a haptic signal is coupled with the control shaft. The device is an electric motor which exercises a torque on the control shaft that opposes the rotational motion when applied correspondingly. Varying haptic signals can be provided as a function of the control or activation of the motor, both with respect to the amperage applied to the motor as well as a function of the current setting of the angle of rotation of the control shaft. The actuator also can be operated without controlling the motor and thus without a haptic signal which drives the rotational motion.
Therefore, it is possible that the same rotating actuator can be operated both with and without a predetermined haptic signal or with varying haptic signals as a function of the respective mode of the rotating actuator. This is advantageous compared with those rotating actuators that are provided with a haptic signal generating device in the form of a mechanical latching or notching assembly having an annular body and at least one detent element engaging the inside of the annular body in order to generate a haptic signal when rotating the handle. With this type of mechanical tactile haptic signal generating device, the haptic signal cannot be switched on or off, and, above all, cannot be reversed.
In contrast to the mechanical haptic signal generating devices, which are developed in the form of a mechanical stopping device, the above-mentioned rotating actuator is considered disadvantageous because the zero position of the rotating actuator is relatively soft, and a control vibration can be felt as a result of the load moment when rotating the handle, which the motor necessarily must produce.
It is an object of the present invention to develop a generic rotating actuator of the aforementioned type having a haptic signal generating device, which operates similar to a mechanical detent assembly, so that the disadvantages mentioned in terms of the above illustrated prior art are avoided.
The foregoing object is realized in the present invention in that an activating device is allocated to the haptic signal generating device, which is designed as an annular body having teeth on an inner surface and at least as one detent element. By selecting the activation device, an interaction is created between a detent element and the annular body in order to generate the haptic signal formed by the teeth of the annular body. The interaction between the detent element and the annular body, and consequently, the haptic signal formed by the teeth of the annular body, can be enabled or disabled by activating or deactivating the activation device as the control shaft is rotated.
The rotating actuator in accordance with the present invention is based on an actuator whose haptic signal generating device is formed similar to a mechanical detent assembly. The result is a precise, predetermined haptic signal that is produced when the control shaft rotates. The rotating actuator also includes an electromagnetically operated activation device. The activation device acts upon at least one of the two detent devicesxe2x80x94annular body or detent elementxe2x80x94which interact to generate the haptic signal. By activating or deactivating the activation device, the interaction between the annular body and a detent element can be connected or disconnected.
The activation device can be designed, for example, to act upon a detent element to engage the detent element depending on the design of the activation device when activating the annular body to be lifted from the annular body. The activation device may correspondingly also be effectively positioned on the annular body carrying the teeth. With this embodiment, at least one spring pre-loaded stop element engages the teeth of the annular body. The inner surface of the annular body concentrically surrounds the control shaft. Without actuating the activation device, the annular body also is moved corresponding to the rotational motion of the control shaft as a result of the detent element engaging the inside of the annular body as the control shaft rotates so that no haptic signal is perceivable in this mode of the rotating actuator.
Only when selecting the activation device, the annular body carrying the teeth is determined in contrast to a rotational motion of the rotating control shaft, so that subsequently at least one detent element is guided via the teeth of the annular body for generating the desired haptic signal as the control shaft rotates. Such an embodiment has the advantage that undesired motions of the control shaft can be avoided when switching from one haptic signal to another haptic signal, which potentially result from a stop element failing to exactly engage a recess in the inside surface of the annular body. These types of haptic signal related motions of the control shaft are undesirable in many applications.
The rotating actuator in accordance with the present invention thus includes a mechanical connectable and disconnectable haptic perception signal. A further embodiment of the present invention provides that the haptic signal generating device includes one or several additional annular bodies and at least one additional detent element which engages the interior of respective detent curves, in which these additional devices also are allocated to an activation device in order to connect or disconnect the haptic signal. The stopping devices (i.e., annular bodies and detent elements) may also be placed concentrically to each other or provided in different layers above each other, so that such a rotating actuator may include different haptic perception signal generators. Further, it can be provided that each mechanically provided haptic signal generator can be interconnected overlaying either individually or in groups.
In a preferred embodiment, it is provided that the activation device acts upon the annular body, which carries the teeth at the inside surface, and fixes and engages the annular body by friction compared with the rotational movement of the control shaft when activating the activation device. Furthermore, it can be provided that such an annular body, for example, can be fixed by a positive locking gear by means of the activation device and its control compared with a rotational movement of the control shaft.
For example, an electromagnetically activated tension ring, developed in the form of a hose clamp, may serve to produce a friction engaged connection between an annular body carrying the teeth and the activation device. When the activation device is activated, the annular body can be fixed in the tension ring such that the teeth remain in a fixed position compared with a rotational movement of at least one detent element engaging the inner surface of the annular body.
However, another activation device is used in a further development which does not act upon an annular body carrying the teeth, but acts directly upon the control shaft, suitably upon a brake flange, which is connected with the control shaft. By means of this activation device, the rotational motion of the control shaft can be blocked or, if desired, the necessary torque for moving the control shaft can be increased. For example, this additional activation device is able to realize a tactile stop in the event that such a stop is to withstand greater forces. It also is suitable to design this activation device, which acts upon the control shaft, to produce a positive-locking connection between the two elements (i.e., the activation device and the control shaft). Furthermore, there is the option of providing a rotating actuator without a haptic signal generating device or with a haptic signal generating device of a different type solely with an activating device, which directly acts upon the control shaft.